Why doesn't my battery charge when inverter is on?

DIY
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1

New to solar. Have my 48v batteries connected to a basic 1500/3500 48v inverter. Battery charges during the day if the inverter is off but as soon as you turn on voltage drops to 0 and stops charging. Battery will stay the same throughout the day until the sun goes down. It almost acts as a pass through. 550w of solar coming in and using about 200-300w at max on inverter when on but battery doesn’t change.

How can a fix this and get to charge and use inverter at the same time? or what do I need to purchase to make it work? Sorry for the newbie question. Thanks

2

Please post more details about your system components and how they are connected..
Have you checked your battery with a volt meter?
What type of battery is it?

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Connected in parallel with 2 48v 100a batteries

Battery 1 53.88v

Battery 2 53.79v

4

OK, so :

  1. Main battery isolator switch: First on I’ve seen with both positive and negative cables going to the switch. Normally these are single pole, so no wiring slips can cause an accidental short. Do check the wiring.
  2. The type of circuit breaker used in the PV positive may be unreliable - bolted megafuse is better for this type of application.
    you should have a mutltimeter, or hopefully a dc clamp ammeter:
    when the sun is up you can use the VE connect or the ammeter to measure the charge going into the batteries. If this si very low, check to see that you are under the maximum permitted voltage of the battery type. Set the lower voltage in the MPPT abs voltage.
    When the sun is down or turn the PV panels off:
    Measure the battery voltage at the battery terminals, then at the busbar.
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